A METHOD FOR COOLING AND STORING FOOD ITEMS

Abstract

The invention provides a method for cooling, transporting and storing wet food product without using ice for the transport and the storage using a new method of cooling the food products below zero to prolong shelf-life and quality of the product. Furthermore, the present invention provides a new method for delivering a fresh food product to the market with reduced water footprint and carbon footprint.

Claims

1. A method of cooling and storing and wet food product, comprising: a) undercooling the product by submerging in salt solution at a sub-zero temperature at or above the freezing point of the solution, while the solution is agitated in order to prevent formation of ice shell or crust on the product, b) removing the product from the solution and placing in storing receptacle, c) storing the product in the storing receptacle within a space which is maintained at a temperature within the range of about 4 to 0 C.

2. The method of claim 1, wherein the method further comprises step d) of transporting the wet food product in the storing receptacle within a space which is maintained at a temperature within the range of about 4 to 0 C.

3. The method of claim 1, wherein the wet food product is undercooled in step a) until the product has reached a homogenous temperature within a range from about 3 C. to about 0.1 C., and preferably within the range from about 2 C. to about 0.1 C.

4. The method according to claim 1, wherein the undercooling step is performed in a salt-controlled and temperature-controlled solution in at least two steps of: i) placing the wet food product in first salt-controlled and temperature controlled solution having a salt concentration in the range from 0.1 to 10% and a temperature in the range from +1 to 3 C., where the salt concentration and set temperatures of the salt-controlled and temperature controlled solution brings the homogenous temperature of the fish to +2 to 1 C., and ii) transferring the wet food product to a second salt-controlled and temperature controlled solution having a salt concentration in the range from 1 to 20% and a temperature in the range from 1 to 12 C., where the salt concentration and set temperatures of the salt-controlled and temperature controlled solution brings the homogenous temperature of the fish to 0.1 to 3 C.

5. The method according to claim 4, wherein the temperature of the solution is maintained at a temperature which is at least about 1.0 C. higher than the freezing point of the solution, and preferably at least about 1.5 C. higher.

6. The method of claim 1, wherein the product is selected from freshly slaughtered fish, freshly slaughtered chicken, beef, pork and lamb meat products.

7. The method of claim 6, wherein the product is fish selected from salmon, trout, cod, haddock, pollock, catfish, ling, blue ling, tusk, monkfish, carp, bass, bream, turbot, sea bass, sole, milkfish, grey mullet, grouper, sea bream, halibut, flounder, Japanese flounder.

8. The method according to claim 4, wherein the fish has been gutted and/or bled prior to the step of undercooling.

9. The method of claim 1, wherein said packaging comprises a double-layered box of a material in thin layers.

10. The method of claim 1, wherein said double-layered box is configured and folded so as not to leak liquid while in upright position.

11. The method of claim 1, wherein said space in step c) is maintained at a temperature within the range from about 0.5 to about 2 C.

12. The method of claim 1, wherein the temperature range of the space in steps c) and d) is the main source of maintaining the temperature of the food product below freezing.

13. The method according to claim 1, wherein a small amount of ice or liquid is placed in the storing receptacle.

14. The method of claim 1, wherein the period of storing and/or transporting the wet food products within a space which is maintained at a temperature within the range of about 4 to 0 C. is from 1 hour to 7 days.

15. A method of reducing the environmental footprint comprising a water footprint and a carbon footprint of a wet food product comprising: a) undercooling the wet product by submerging in salt solution at a sub-zero temperature at or above the freezing point of the solution, while the solution is agitated in order to prevent formation of ice shell or crust on the product, b) removing the product from the solution and placing in a storing receptacle, c) storing the product in the storing receptacle within a space which is maintained at a temperature within the range of about 4 to 0 C., and d) transporting the product in the storing receptacle within a space which is maintained at a temperature within the range of about 4 to 0 C.

Description

DESCRIPTION OF THE INVENTION

[0019] In the present context the term under-cooling or sub-chilling refers to the process or method of bringing fish to a desired temperature at or near the phase transition of freezing the fish without freezing the fish, and generally below the freezing point of water (0 C.). Furthermore, these terms refer to a fish or fish product being brought to or kept at a desired temperature at or near the phase transition of freezing the fish without freezing the fish, such as a temperature below 0 C. (sub-zero conditions), such as preferably at or below 0.2 C., or more preferably at or below 0.5 C., or at or below 0.7 C., or at or below 0.8 C., such as at or below 1.0 C., such as at or below 1.5 C.

[0020] In the present context the terms wet food product, food product or product are used equally and relate to a food product selected from freshly slaughtered fish, freshly slaughtered chicken, beef, pork and lamb meat products.

[0021] In the present context the term fish or whole fish relates to a fish which is either freshly caught and unprocessed at all or cut and/or bled and/or gutted and/or washed and/or graded and/or de-headed and/or the tail has been removed or any combination thereof.

[0022] In the present context the terms storing receptacle or package refers to any means of storing and/or transporting food product, such as but not limited to tubs or bulk containers for transporting fish, trays, plastic or cardboard boxes . . . .

[0023] In the present context the term ice reduced or ice-free manner refers to the placement of under-cooled or sub-chilled wet food product in a storing receptacle in a facility where the surrounding temperature is at least below 0 C., where no additional cooling media is required in the storing receptacle to keep the wet food product at a desired temperature. The term ice reduced manner refers to a way of storing and transporting such food products where a small amount if ice is distributed in the storage container f.ex. as a reference that the food products were kept below 0 C.

[0024] Carbon footprint (CO2e) is defined herein as the release of all greenhouse gases calculated to CO2 during the steps of production and processing of the raw materials, manufacture and packaging of the food product and logistics relating to all these steps. Thus the carbon footprint includes CO2e from all the steps of the life cycle until the product is available to the consumer.

[0025] Water footprint is defined herein as consumption of freshwater resources during all the same steps as mentioned above until the product is put on sale to the consumer.

[0026] The carbon and water footprints may be referred to as environmental footprints.

[0027] In an embodiment of the present invention the product is fish selected from salmon, trout, cod, haddock, pollock, catfish, ling, blue ling, tusk, monkfish, carp, bass, bream, turbot, sea bass, sole, milkfish, grey mullet, grouper, sea bream, halibut, flounder, Japanese flounder.

[0028] In an embodiment of the present invention the fish is gutted and/or bled prior to the step of undercooling.

[0029] In an embodiment of the present invention the salt concentration and set temperatures of the salt-controlled and temperature controlled solution(s) for each step in the pre-cooling and under-cooling are based on the type of meat or species of fish, size and fat content of the fish being brought to an under-cooled state.

[0030] In an embodiment of the present invention the time for each step in under-cooling is based on the species, size, as well as the fat content of the fish and the quantity of the fish being cooled. In one embodiment, freshly caught cod, slaughtered, gutted and bled is first cooled for 40-50 minutes at a set temperature of 1 C. in a solution of 3% salt concentration and then transferred to a solution of 7% salt concentration set at a temperature of 3 C. preferably for about 15 minutes. Salmon has more fat content, so slaughtered, gutted and bled salmon of same size is in one embodiment cooled for 60 minutes at a set temperature of 1 C. in a solution of 3% salt concentration and then transferred to a solution of 8% salt concentration set at a temperature of 4.5 C. for 25 minutes.

[0031] In an embodiment of the present invention the food product is further transported in the ice-free or ice reduced package within a space which is maintained at a temperature within the range of about 4 to 0 C.

[0032] In an embodiment of the present invention the food product is undercooled in step a) until the product has reached a homogenous temperature within a range from about 3 C. to about 0.1 C., and preferably within the range from about 2 C. to about 0.1 C.

[0033] In an embodiment of the present invention a continuous movement or agitating of the wet food product in the salt solution is provided during the step of bringing the wet food product to an under-cooled state to prevent the surface of the wet food product from freezing and to prevent the formation of shell or crust at the surface of it during the cooling process. The continuous movement of the wet food product in the solution speeds up the cooling process and allows the use of a cooling solution at a warmer temperature, such as close to the target temperature at a certain cooling step.

[0034] In an embodiment of the present invention the wet food product is maintained at a temperature above freezing point of the wet food product, but at or near the phase transition temperature of freezing the wet food product without freezing it, such as at a temperature in the range from between about 0.5 to about 2 C. during storing, transfer and processing, such as at about 0.5 C., about 1 C., or about 1.5 C.

[0035] In an embodiment of the present invention the temperature of the salt solution is maintained at a temperature which is at least about 1,0 C. higher than the freezing point of the solution, and preferably at least about 1.5 C. higher.

[0036] In an embodiment of the present invention the wet food product is brought to a homogenous temperature in the range between 0.2 and 4.0 C., such as a temperature in the range from about 0.5 C., such as from about 0.8 C., such as from about 1.0 C. or from about 1.2 C., to about 4.0 C., or to about 3.5 C., such to about 3.0 C., or to about 2.5 C. In the present context the term homogenous temperature refers to equalised average temperature which is measured from 0 to 120 minutes after a cooling process.

[0037] In an embodiment of the present invention the packaging comprises a double-layered box of a material in thin layers.

[0038] In an embodiment of the present invention the double-layered box is configured and folded so as not to leak liquid while in upright position. In a specific embodiment of the present invention the double-layered box is a double-layered cardboard box.

[0039] In an embodiment of the present invention the space in step c) is maintained at a temperature within the range from about 0.5 to about 2 C.

[0040] In an embodiment of the present invention the temperature range of the space in steps c) and d) is the main source of maintaining the temperature of the food product below freezing.

[0041] In an embodiment of the present invention a small amount of ice or liquid is placed in the storing receptacle.

[0042] In an embodiment of the present invention the period of storing and/or transporting the wet food products within a space which is maintained at a temperature within the range of about 4 to 0 C. is from 1 hour to 7 days, such as from 12 hrs to 5 days, or from about 1 day to 3 days, or from about 2 to 6 days.

EXAMPLES

Example 1

Analysis of the Difference Between Sub-Chilling and Traditional Chilling of Salmon

[0043] Salmon was taken just after slaughtering and chilled either by using ice (traditional) or by the sub-chilling method of the present invention. The sub-chilled salmon was chilled in a screw-container for 1 hr in a two-step process, where it was first brought into a solution with a temperature of 1 C. and then further to 4 C. Thereafter the salmon was stored at 1.5 for 4 days. The salmon receiving traditional treatment was chilled on ice for 4 days in EPS boxes. Further processing of Salmon 4 days after slaughtering showed that the fish was easy to process and had a good resistance to heading and filleting processes resulting in higher yield (Fig not shown)

[0044] Table 1 shows the temperature of the fillets after 2, 4 and 6 days as well as softness and gaping.

TABLE-US-00001 TABLE 1 Days 2 4 6 Sub Tradi- Sub Tradi- Sub Tradi- Chilled tional Chilled tional Chilled tional Temp C. 1.5 0 1.5 1 1.5 0.2 Softness 0 1 0 1 0 2 Gaping 0 2 0 3 0 4 Rigor yes No Yes No No No

[0045] The results show that the sub-chilled salmon maintains a homogenous temperature of 1.5 C., whereas the traditionally chilled salmon reaches higher temperature, becomes softer and shows increased gaping. The traditionally chilled salmon also starts to get softer, whereas the sub-chilled salmon maintains stiffness.

[0046] FIG. 1 shows pin bone removal while salmon is in rigor and how pin bones car be removed without damaging fillet. FIG. 1A shows a salmon fillet after pin bone removal. The fillet looks fine and undamaged. FIG. 1B shows two bones, on top a bone removed from a salmon after traditional chilling and below a bone removed from a salmon after sub-chilling. No flesh is attached to the bone from the salmon chilled with sub-chilling, but flesh is attached to the salmon bone chilled with traditional chilling. FIG. 1C shows a comparison of two fillets after pin bone removal. On the left is a fillet, which was chilled by traditional chilling and on the right is a fillet chilled by sub-chilling. The fillet chilled by traditional chilling is damaged after the bin bone removal, whereas the fillet chilled by sub-chilling has very little damage.

Example 2

Product Shelf Life of Salmon with Sub-Chilling and Traditional Chilling

[0047] Product shelf life of the salmon was also examined based on the chilling method. Table 2 shows bacterial count comparison between salmons chilled by traditional vs. the sub-chilling method.

TABLE-US-00002 TABLE 2 Total count Black colonies/g Days Sub-Chilled Traditional Sub-Chilled Traditional 2 <10.000 20.000 <10.000 <10.000 6 <10.000 <10.000 <10.000 <10.000 10 20.000 <10.000 <10.000 <10.000 16 20.000 300.000 <10.000 30.000 21 2.100.000 39.000.000 20.000 910.000

[0048] The results show that the sub-chilling method extends shelf life dramatically.

[0049] FIG. 2 shows temperature monitoring during transport and processing of salmon chilled by traditional method and sub-chilling method. Sub chilled salmon maintains a temperature of 1.5 C. The temperature of the fish remains stable and the Salmon is in Rigor the whole throughout the process. The traditionally chilled salmon never enters sub-zero conditions and takes longer to cool down.

[0050] FIG. 3 shows different ways of packing freshly slaughtered gutted fish. FIG. 3A shows whole salmon packed in a Styrofoam box which needs to be filled with ice to keep the product cold. FIG. 3B shows on the left traditional packing for transport in a tub with ice and on the right salmon chilled by the method of the present invention and packed in an ice-free manner in a tub.

[0051] FIG. 4 shows what the salmon looks like after having been packed and transported on ice in a tub (above) and what the salmon looks like after being cooled, packed and transported according to the present invention with under-cooling and ice-free transport in a tub. The salmon transported by the present method has no pressure damage because of the ice in the tub and the fish is stronger.

[0052] As used herein, including in the claims, singular forms of terms are to be construed as also including the plural form and vice versa, unless the context indicates otherwise. Thus, it should be noted that as used herein, the singular forms a, an, and the include plural references unless the context clearly dictates otherwise.

[0053] Throughout the description and claims, the terms comprise, including, having, and contain and their variations should be understood as meaning including but not limited to, and are not intended to exclude other components.

[0054] The present invention also covers the exact terms, features, values and ranges etc. in case these terms, features, values and ranges etc. are used in conjunction with terms such as about, around, generally, substantially, essentially, at least etc. (i.e., about 3 shall also cover exactly 3 or substantially constant shall also cover exactly constant).

[0055] The term at least one should be understood as meaning one or more, and therefore includes both embodiments that include one or multiple components. Furthermore, dependent claims that refer to independent claims that describe features with at least one have the same meaning, both when the feature is referred to as the and the at least one.

[0056] It will be appreciated that variations to the foregoing embodiments of the invention can be made while still falling within the scope of the invention can be made while still falling within scope of the invention. Features disclosed in the specification, unless stated otherwise, can be replaced by alternative features serving the same, equivalent or similar purpose. Thus, unless stated otherwise, each feature disclosed represents one example of a generic series of equivalent or similar features.

[0057] Use of exemplary language, such as for instance, such as, for example and the like, is merely intended to better illustrate the invention and does not indicate a limitation on the scope of the invention unless so claimed. Any steps described in the specification may be performed in any order or simultaneously, unless the context clearly indicates otherwise.

[0058] All of the features and/or steps disclosed in the specification can be combined in any combination, except for combinations where at least some of the features and/or steps are mutually exclusive. In particular, preferred features of the invention are applicable to all aspects of the invention and may be used in any combination.